Going by the bottom photo, the unit has a decent paint-job with no rust spots showing through. Suggesting it has been cared for reasonably well, and might be in decent condition generally. In which case it would be a pity if it was just cut up!

As for what model it is… Not having an Alco S on a turntable to view from the camera angle shown I can't be sure, but it LOOKS as if the radiator is the short one used on S1/S3, not the longer one on S2/S4: somebody with a better eye than mine, or a photo collection that includes some taken from this angle, could confirm or refute this. The basic engine BLOCK is pretty much the same, and de-turbo-ing an S2's engine before reinstalling it in an S1 shouldn't have been beyond the abilities of Relco's shop.

Further evidence that, whatever the engine inside it, the visible carbody is an S1.An S2 has eight doors along the (left) side of th hood between the cab and the radiator, an S1 with its shorter radiator has nine. I count nine in the photo.